Implantable medical devices are commonly used today to treat conditions such as cardiac arrhythmias, pain, incontinence, sleep disorders, and movement disorders such as Parkinson's disease and epilepsy. One known type of implantable medical device, a neurostimulator, delivers mild electrical impulses to neural tissue through an array of electrodes. Typically, such devices are part of totally implantable stimulation systems and may be controlled by a physician or a patient through the use of an external programmer connected to the device, for example, via telemetry. This type of device generally includes a power source and a pulse generator contained in a hermetically sealed enclosure. Such a system may also include a lead extension, and a stimulation lead, of which the aforementioned array of electrodes is an integral part. An electrode assembly of the lead may be located in proximity to a distal end thereof, and include from four to eight electrodes arranged in the array. A proximal end of the lead may connect to the extension, which electrically couples the lead to the pulse generator of the device, for example, by being plugged into a connector module of the device.
FIG. 1 is a schematic showing an example of a stimulation system, like that described above, implanted in a patient 28 for spinal cord stimulation. FIG. 1 illustrates a device 20 of the system being implanted in an abdominal region of patient 28, and a lead 24 of the system extending along a spinal cord 30, and being electrically coupled to device 20 via an extension 22, which is shown connected to lead 24 by a connector 32. FIG. 1 further illustrates lead 24 including an electrode array 26 positioned along spinal cord 30, for example, having been percutaneously introduced through a needle and into an epidural space that surrounds spinal cord 30. Although a variety of known electrode assemblies are suitable for arrays like electrode array 26, there is still a need for new assemblies.